1. Field of the Invention
The present invention relates generally to computer software, and more specifically to IMS software.
2. Description of the Related Art
By some estimates, nearly seventy percent (70%) of corporate data in the United States and abroad resides on mainframe computers, e.g., S/390 mainframes manufactured by International Business Machines. Moreover, business-to-business (B2B) e-commerce is expected to grow at least five times faster than the rate of business-to-consumer (B2C) e-commerce. Many transactions involving this corporate data can be initiated by Windows/NT servers, UNIX servers, and other servers but the transactions must be completed on the mainframe using existing legacy applications residing thereon.
One group of legacy applications are the message format service-based information management system applications (“MFS-based IMS applications”) on which many businesses depend heavily. MFS is a facility of the IMS transaction management environment that formats messages to and from many different types of terminal devices. As businesses upgrade their technologies to exploit new B2B technologies, there is a requirement for an easy and effective method for upgrading existing MFS applications to include e-business capabilities. One such e-business capability is the ability to send and receive MFS-based IMS transaction messages using thin-client software operating on a variety of devices. In addition, it is desirable to send and receive MFS-based IMS transaction messages using extensible Markup Language (XML) documents.
The MFS language utility compiles MFS source, generates MFS control blocks in a proprietary format, known as Message Input/Output Descriptors (MID/MOD), and places them in an IMS format library. MFS supports several terminal types, e.g., IBM 3270 terminals, and it was designed so that the IMS application programs using MFS do not have to deal with any device-specific characteristics in the input or output messages. Because MFS provides headers, page numbers, operator instructions, and other literals to the device, the application's input and output messages can be built without having to pass these format literals. MFS identifies all fields in the message response and formats these fields according to the specific device type. This allows application programmers to concentrate their efforts on the business logic of the programs.
Because the IMS application program input/output data structures do not fully describe the end user interaction with these existing MFS applications, there exists a need for dealing with information that is buried within various MFS statements. Examples of this information includes 3270 screen attribute bytes and preset function key (PFKey) input data. Many MFS-based IMS application programs are passed PFKey data in input messages, but application logic is not required to recognize that a certain PFKey was pressed and a literal corresponding to that PFKey must be inserted into the input message. This is due to the fact that, at runtime, it is the MFS online processing and not the application that places the literal that corresponds to the PFKey pressed into the appropriate field in the input message.
MFS-based IMS application programs predominately include conversational transactions between a client and the MFS-based IMS application program. Conversational transactions are transactions in which the status of the transaction is maintained beyond a single request and response exchange. Conversational transactions typically include a plurality of request and response exchanges to complete the transaction.
XML has become the preferred data format to support thin-software clients, Web services, B2C and B2B interchanges. However, presently, there seems to be a need for software to handle preprocessing, processing, and formatting of MFS-based commands, especially to support conversational transactions. Furthermore, there appears to not exist a way for HyperText Transfer Protocol (HTTP) requests to be presented to an MFS-based IMS application and HTTP responses returned.
Accordingly, there is a need for a system, method, and apparatus which will facilitate conversational transactions between thin-client software and MFS-based IMS applications. The conversational transactions could be managed for a plurality of MFS-based IMS applications by a central system, method, or apparatus. In a business-to-consumer environment, the conversational transactions may be conducted via an Internet browser or other thin-client. The system, method, and apparatus should manage paging requests made by a user and format output based on progress of a user through physical pages of one or more logical pages for an MFS-based IMS application.